do you ever find yourself wishing you had more overlap or not? Do you ever find yourself in the situation where you have to keep shifting the front ring to deal with the terrain?
I have issues with the 34 (other than for climbing), I find it of little use around here, its too small. Before anyone gets on my case the 9 speed that I run, the 15-12 causes too much crossover (with standard DA derailleurs) So you are left with 23-17 which is pretty high gearing, however this problem is off set by the 50 which works great even for some of the crits and lumpy road races. Caveat I only experienced the compacts on a road bike.
I’d have to say no to both your questions. I have them on my road bike and the 34 is the cat’s meow on our Thursday night hill ride.
The main issue I have with compacts is that in relatively flat terrain - going around 18-22 mph - I am either in the 34-13/14 or the 50-17/18/19 = not the best chainlines. I’ve never had a problem with a poor chainline but it is a poor chainline…whatever that does…
I don’t switch frequently from the 50 to 34 but I can see having to shift a lot on a rolling course where you go up and down shorter hills…but it shifts well from 50 to 34. Not sure if its that different from having a 52-39.
Although I did a rolling course yesterday and my front derailleur was messed up so I had to stay in a 42 for the last 2/3rds of the course and that worked o.k.
I mainly like the 34 for steep hills in training or racing long course where I do not want to spike my watts…
Dave
I love the 34, it is quite hilly where I generally ride (smallest gear is 34x26 on 700’s). I tend to ride higher RPM so I am planning to reduce my big chainring to a 48 this week. I have been riding on a 50 tooth large ring on conventional cranks now for 5 years before I got my compact crankset last summer. In tris I coast above 60 kph, so by going to a 48, I can still ride at 58 kph at 110 RPM or so in a 12 tooth cog (0.7mpi110*(48/12)/1000).
What this will also allow me to do is pretty well stay in the large chainring for most hills when racing and not have to flip back and forth from big to small. In a 48/25 at 80 RPM, the speed is 20 kph. So by staying in the big ring only with a 48, I can service a range of speed from 20 kph to almost 60 kph by using all my gears in the back and varying my RPM from 80 to 112 RPM or so. Sounds like a good deal to me. Then when I get into some really serious hills, its over to the 34. There are few races that I do, where the speed is below 20 kph (12 mph) for large periods of time, although I see sub 20 kph speeds often in training especially in the hills.
I think if you are roadie stud, you need a 53 to contest sprints at crits etc. For your run of the mill age grouper, a 48 is actually quite fine. This also reduces the overlap issue that Marco speaks of. To put this in perspective, my Olympic tri bike PB in 59 min on a flat course and half Ironman in 2:24 on a hilly course.
Dev
I have them on my TT/Tri bike. They work out great. I never have issues with wanting mroe overlap. Shifting a lot, is not a problem. Shifting is at my fingertips, so it is not an issue.
For a tri bike, they are great.
I have one. I hate it. FSA, first version (not the new MegaExo with integrated BB). I think the workmanship is not as good. And I have much more trouble finding the right gear than with my 53/39.
I much prefer 53/39 + 12/27 (12/23 for flats courses) to 50/34 + 12/23.
I might be happier with the Campy one over my FSA, since I am not pleased with FSA craftsmanship (especially the chainrings, which are wimpy). But I still think the gearing is not a good as on my “regular” pairing…
Why in the world would you want a compact crankset for a TT ?? I was under theimpression they were for training in just in case people are under powered, but why would you not want to push a big gear in racing ??
Just a question as I can’t understand this compact crank fad.
Trev
why would you not want to push a big gear in racing??
I don’t think all TTs are on a flat course…
Tyler Hamilton is NOT underpowered… Maybe small, but still massive wattage. He was really the one to make the compact a seller when he won a solo stage (w/ a broken collarbone) on them.
Some people find a better sweet spot with a compact. Just as some find it with massive gears (Bjorn). It is right for some, not right for others. Not everyone fits with 53/39, and finally there are some options for smaller gears (instead of just bigger). It means you can play around and find gear ratios that work for you.
I found for road racing that sometime the lack of overlap meant I would be wandering between my big and small rings on climbs. I also found that once I was in good race shape that the 34 was an overkill for me on climbs. I have since swapped to a 52/38 and an 11-23 for the vast majority of my courses.
I dont regret getting the compacts as for some particularly steep and heinous climbs with extended pitches of 10-12% a 50-34 with an 11-23 gives me similar range with less gaps between gears than a 12-27 and a 53-39. I like to have the compact gear option even if I dont use it a lot.
based on a quick calculation 50x11 gives 308 gear cm which translates to about 52km per hr @ 90rpm, that is plenty amount of gear for anyone other than a serious roadie even then a “normal” 53x12 gives you 299 gc and 50km/ph @ 90rpm. So for most contested sprints that is what the Cat1/2 guys I train with (at least start out with) race on.
I’ve been on the FSA compact cranks for over a year now, and I love them. I also ride 650c wheels. Now I don’t know about you world record holders out there, but when I’m spinning my 50/11, I’m going 33 to 38mph. That seems to be pleanty of speed for a guy that wants to break an hour for his/her 40k. Why I really like the gearing is that the jumps are so small, that you can keep that cadence sweetspot within a few revs. I live in the mountains, so the 34 is a godsend, especially when the wind blows down the mountain. More than likely if you have trouble with this gearing, it a function of the cadence you have trained yourself to ride in. I have been in only one condition where I needed more gearing, and that was a flat 30mph tailwind. I talked to some FSA guys at wildflower, and they now have a 52/36 set up. As soon as I get fit enough to ride a 57 or better, I’ll probably step up to it…
Until I start turning over a 53/11 in a TT, I like the compacts. I am turning over the 14t now in flat TTs. For tris I can easily spin up the climbs with a 34/21 (I use a 12-21) if I need that much gear (like AIT).
If you turn over your gears at a real slow RPM, then you might run out of gear. If you always turn the 53/11, then a compact is not for you. I race with it and love it.
As one poster noted, they’re not quite as nice for flat land cruising at 18mph or so- you’re right on the boundary of the cross-chaining that you want to avoid. But I love mine for the riding I do around here. Almost all of the downhills are steep twisty things that you’re not going to be pedalling on anyway, and the uphills can be…challenging.
Apparently I am weak compared to all of you since I ride a 50x34 with a 12-27 on back for my road bike. And I use every bit of those gears. I also have a habit of taking my road bike up climbs where you have to stay seated to keep your traction in the dirt. Small gears can be a godsend.
J
I have a 50/36 setup on my bike and I love it! I put the 34 back on for long hard climbing rides, but the 36 is good for 95% or so of my riding and racing.
I actually find my self shifting less than with my old setup.
I also have the 50/36 with an 11-23 most of the time. I do find I shift a fair bit from the small ring to the big ring on rollers, but the shifting is good, so that’s okay. I also have no problems riding the 50/23 and the 36/11 so that helps minimize the front shifts.
I’m real happy with this setup, especially since I can always run a 12-25 for really hilly courses (haven’t needed to yet and I run an 11-21 for flatter courses) and a 50/12 is still more than 30 mph.
I’ve got the FSA carbon compact on my new tri bike. I was worried about hills and contemplated a triple (I’m a girl and have a couple hilly races coming up) but the shop sold me on the compact 34-50 with 12-25. I like the gearing but the the 50 keeps warping. I took it back to the shop and they straightened it but now it’s warping again. I’m really not impressed with FSA.
I’m thinking of replacing it with another brand. I’m not up on all the manufactures of compacts so who else makes a good compact?
That is odd. I have had a FSA carbon compact crank on my bike for over a year, and a good 3000 miles without a problem. I spend most of my time in the 50, and it is still good. I think that straightening a chainring isn’t such a good idea and it probably should have been replaced.
I agree, it should be warranteed through FSA. I have around 2,000km on my FSA compact cranks and have no problems. They have handled some of my big ring drills early in the season and most of it is racing.
Ask the shop to replace the cranks. If they do not want to do it, call FSA and tell them about your problem.